Password Generator — Free Online Strong Password Creator

How to Use the Password Generator

1. Set your desired password length: Use the Password Length field to choose how many characters your password should contain. The default of 16 characters provides strong security for most online accounts, but for banking, email, or cloud storage, consider increasing to 20 or more characters. Each additional character exponentially increases the total number of possible combinations.
2. Select which character types to include: Toggle the switches for uppercase letters, lowercase letters, numbers, and symbols. Keeping all four enabled maximizes your character pool and entropy. If you need to type the password manually, such as for a Wi-Fi network, enable the Exclude Ambiguous Characters option to avoid confusing characters like zero and the letter O.
3. Generate and regenerate: The tool creates a password immediately based on your current settings. If you want a different random password with the same configuration, click the Regenerate Password button. Each click produces a completely new random combination using cryptographic randomness from your browser.
4. Copy your password: Click the Copy button to save the generated password to your clipboard. Paste it into your account registration page or password manager. The results panel shows the strength rating, entropy in bits, and estimated time it would take to crack the password through brute force, so you can verify your password meets your security needs.

All password generation happens locally in your browser. No passwords are sent to any server, ensuring your generated credentials remain completely private and secure.

How Password Strength Is Calculated

Variables Explained

• Password Length: The number of characters in the generated password. Longer passwords are exponentially more secure because each added character multiplies the total possible combinations by the size of the character pool.
• Character Pool Size: The total number of unique characters available for each position. With all types enabled and no exclusions, the pool includes 26 lowercase, 26 uppercase, 10 digits, and 26 symbols for a total of approximately 88 characters. Excluding ambiguous characters reduces this pool slightly.
• Entropy: A measure of randomness expressed in bits. Each bit of entropy doubles the number of possible combinations. The higher the entropy, the stronger the password. Industry benchmarks recommend a minimum of 60 bits for general use and 128 bits for high-security applications.
• Guesses Per Second: The assumed attack rate used to estimate crack time. Our calculator uses 10 billion guesses per second, representing a well-funded attacker using modern GPU hardware. Real-world attacks may be faster or slower depending on the attacker's resources.

Step-by-Step Example

Suppose you generate a 16-character password with uppercase, lowercase, numbers, and symbols enabled (pool size of 88 characters):

1. Calculate entropy: 16 x log2(88) = 16 x 6.46 = 103.3 bits
2. Calculate total combinations: 88^16 = approximately 1.9 x 10^31
3. Calculate crack time: 1.9 x 10^31 / 10^10 = 1.9 x 10^21 seconds = approximately 61 trillion years

With over 103 bits of entropy, this password is rated as strong and would take trillions of years to crack through brute force, making it suitable for even the most sensitive accounts.

Practical Examples

Example 1: Lisa Secures Her Email Account

Lisa realizes she has been using the same simple password across multiple accounts. She decides to start with her primary email, which is the gateway to all her other accounts. She sets the password generator to 20 characters with all character types enabled:

• Password Length: 20 characters
• Character Pool: uppercase + lowercase + numbers + symbols = ~88
• Entropy: 20 x 6.46 = 129.2 bits (Very Strong)
• Estimated Crack Time: Billions of years+

Lisa copies the password and stores it in her password manager. With 129 bits of entropy, her email account is now protected by a password that would take longer than the age of the universe to crack through brute force.

Example 2: Kevin Creates a Wi-Fi Password

Kevin is setting up a new home Wi-Fi network and needs a password that is both secure and easy for guests to type when they visit. He enables the Exclude Ambiguous Characters option so no one confuses O with 0 or l with 1:

• Password Length: 14 characters
• Character Pool: uppercase + lowercase + numbers (no symbols, excluding ambiguous) = ~54
• Entropy: 14 x 5.75 = 80.5 bits (Strong)
• Estimated Crack Time: Thousands of years

The generated password is easy to read aloud and type on any device, while still providing strong protection for his home network. Kevin prints it on a small card for guests rather than using a simple, guessable password.

Example 3: Rachel Generates Passwords for Her Team

Rachel manages IT for a small business and needs to create initial passwords for five new employee accounts. Company policy requires passwords with at least 100 bits of entropy. She configures the generator for maximum security:

• Password Length: 16 characters
• Character Pool: all types enabled = ~88
• Entropy: 16 x 6.46 = 103.3 bits (Strong)
• Estimated Crack Time: Trillions of years

Rachel generates five unique passwords by clicking Regenerate each time. She distributes them securely through the company's encrypted messaging system and instructs each employee to change their password after first login using our generator for their personal replacement.

Example 4: Marcus Creates an API Key

Marcus is a developer who needs a secure random string to use as an API key for his application. He needs maximum entropy and uses only alphanumeric characters since the API framework does not support special characters in keys:

• Password Length: 32 characters
• Character Pool: uppercase + lowercase + numbers only = 62
• Entropy: 32 x 5.95 = 190.5 bits (Very Strong)
• Estimated Crack Time: Billions of years+

Even without symbols, the 32-character length provides nearly 191 bits of entropy, far exceeding the 128-bit threshold considered uncrackable. Marcus stores the key in his environment variables and uses it for server-to-server authentication.

Password Strength Reference Table

Tips and Complete Guide

Why Random Passwords Beat Human-Created Ones

Humans are inherently bad at creating random passwords. We tend to use predictable patterns like starting with a capital letter, ending with a number, substituting letters with similar-looking numbers (@ for a, 3 for e), and incorporating personal information like birthdays or pet names. Attackers know these patterns and build their cracking dictionaries around them. A password like "P@ssw0rd123!" looks complex but follows every common pattern and can be cracked in seconds.

Cryptographically random passwords, like those our generator creates, have no patterns, no dictionary words, and no personal associations. Each character position is independently random, making them exponentially harder to guess. Even a shorter random password is typically stronger than a longer human-created one because it lacks exploitable patterns.

Using a Password Manager Effectively

Since strong random passwords are impossible to memorize, you should use a password manager to store them securely. A password manager encrypts all your passwords with a single master password, which is the only one you need to remember. Choose a master password that is long (20+ characters) and memorable, perhaps a passphrase of random words. Enable two-factor authentication on your password manager for an additional layer of protection.

With a password manager, you can use a unique strong password for every account without the burden of memorization. If one service suffers a data breach, your other accounts remain safe because no two passwords are the same. Our generator makes it effortless to create a new unique password each time you sign up for a service or need to update credentials.

Two-Factor Authentication as a Security Layer

Even the strongest password provides only one layer of security. Two-factor authentication adds a second verification step, typically a time-based one-time password from an authenticator app or a hardware security key. With two-factor authentication enabled, an attacker who somehow obtains your password still cannot access your account without the second factor. Prioritize enabling two-factor authentication on your email, banking, cloud storage, and social media accounts.

Common Mistakes to Avoid

• Reusing passwords across accounts: If one service is breached, attackers will try that password on every other service you use. Always generate a unique password for every account using our tool.
• Choosing length over all character types: While length is the most important factor, disabling character types unnecessarily reduces entropy. A 12-character password with all types is stronger than a 14-character password using only lowercase letters.
• Storing passwords in plain text: Never save passwords in a text file, spreadsheet, or sticky note. Use an encrypted password manager to store your generated passwords securely.
• Sharing passwords through unencrypted channels: Never send passwords via email, text message, or chat. Use your password manager's secure sharing feature or a temporary encrypted link.
• Ignoring breach notifications: When a service notifies you of a data breach, change your password for that service immediately using our generator. Also change any other accounts where you may have reused that password.

Frequently Asked Questions